This invention relates generally to plural component spray systems, and more particularly relates to a gun which provides external mixing of two components such as catalyst and resin.
In present plural component delivery and spraying systems, one or more of the components is delivered under high pressure to a nozzle for mixing with a catalyst. In addition to the inherent problems of utilizing airless high-pressure delivery systems, assuring a homogeneous mixture is difficult and cross-over of components can occur because of high pressures. The flushing with an expensive flammable solvent is necessary because with internal mixing there is a great chance of resin setup inside the gun from cross-feeding to catalyst passages which could severely damage the gun, or at least render the gun useless until clogged passageways are cleared. After resin has set up, cleaning can be a difficult and time-consuming process if not altogether impossible.